Eradicator starts in normal mode, but can switch to fortress mode.
Even before he got the fortress upgrade, he was handling Cyborg Superman, and seemed about as powerful as Superman (Although this was compared with pre resurrection Superman, so he might be a good deal weaker now..)
This is just standard crazy Black Adam, not WW3 crazy Adam.
I'm thinking of when they had their rematch, after Eradicator came out of his coma and Superman returned to life. Eradicator was pretty much wiping the floor with Cyborg Supes, up until he sacrificed himself protecting Superman from that stream of Kryptonite.